; dx/dt for no tau_0 contribution
;-------------------------------------------------------------

function dxdt_no_tau0, nH, T, GHI, y, xHI, dbg=dbg

  if n_elements(dbg) eq 0 then dbg = 0

  nH = double(nH)
  T  = double(T)
  GHI = double(GHI)
  y = double(y)
  xHI = double(xHI)

  CI = hici_hui( T )
  RC = hiirca_hui( T )

  CI = double(CI)
  RC = double(RC)

  RR = (CI + RC) * nH
  QQ = -( GHI + (CI+2*RC) * nH + (CI+RC) * nH * y )
  PP = RC * nH * (1+y)

  if dbg then begin
      print
      print, 'R: ', RR, format='(A,E30.15)'
      print, 'Q: ', QQ, format='(A,E30.15)'
      print, 'P: ', PP, format='(A,E30.15)'
      print
  endif

  ff = RR * xHI^2 +  QQ * xHI + PP 
  return, ff

end
